Terminal device for pneumatic-dispatch tubes



June l7 1924.

J. G. MACLAREN TERMINAL DEVICE FOR PNEUMATIC DISPATCH TUBES Filed Feb. 23. 1922 2 Sheets-Sheet 1 Samson/Wet. Jwss E. MFIL'LFI HEN.

95 Shier/mug June 17 i924.

J. G. MACLAREN TERMINAL DEVICE FOR PNEUMATIC DISPATCH TUBES Filed Feb. 23, 1 922 gwwewtoz JHME'E' G. MHC'LHREN the general type described has not give Patented June i924,

UNETED STATES JAMES G. MACLAREN, OF IVIAIVIARONECK, NEW/V YORK.

TERMINAL DEVICE FOR- PNEUlVIATIC-DISPATCH TUBES.

Application filed February 23, 1922. Serial No. 538,686.

T0 0 whom it may concern:

Be 1t knownthat 1, JAMES G. MAoLiimiN,

.a citizen of the United States. residing at Mamaroneck, in the county oi lVestchester and State of New York, have invented certain new and useful Improvements in Terminal Devices for Pneumatic-Dispatch Tubes, of which the "following a specification.

This invention relates generally to pneumatic dispatch systems and more particir larly to terminal mechanism for use in single tube installations for two-way tra tiic. In installations of the general type referred to it is necessary that some term of closure or'ga't be provided for closing the end of a dispatch tube following the dispatch of a carrier therein in order to supply motive pressure fluid to the tube in the rear of the carrier. It has been the practice also to provide some form of mechanism for automatically opening the gate, the opening movement being retarded by fluid pressure operated timing mechanism to establish a time interval in which the carrier can travel through the length of the tube. Such pressure operated timing mechanism is operated by fluid pressure taken directly from the tube system, with the result that extraneous and deleterious matter such as moisture, oil, metal flakes and other solid particles have found their way into the tim ing mechanism so that timing mechanism of satis actory results.

It is the object of this invention to provide terminal mechanism of the general type described which willbefree from the objections referred to and'which will pro vide a simple and effective mechanism for the purpose described. 1

With this and other objects in view the invention consists in the provision of terminal mechanism including a gate member arranged to be held in tube closing position by fluid pressure operated means, in

combination with automatically operating gate releasing means set into operation by the act of closing the gratemember and subjected to the retarding influence of a timing device operating independently of the pressure fluid in the transit tub system.

In the drawing in which a preferred embodiment. of the invention is selected for illustration,

F igure 1 is a view in side elevation of a dispatch tube terminal mechanism embodying a preferred form of the invention, show ing the gate member in tube closing position.

Figure 2 is a view in vertical section of th device shown in Figure 1 and showing the gate in its open position.

la igure 3 1s a view in end elevation of the device shown in Figure 1 looking from the left.

Figure 4 is a View similar to Figure 3 looking from the right of Figure 1.

Figure 5 is a plan view looking up from;

tion. At 3 is shown a supply pipe through which fluid pressure is supplied to the dispatch tube 1 in order to propel the carriers therethrough. A valve member cooperating with the seat 5 in chamberfi intowhich the end of the pressure supply pipe 3 empties controls the flow of pressure fluid from the supply pipe 3 through the chamber 7 into the adjacent end of the dispatch tube 1.

In order to close the opening 8 with which the bottom wall 9 of the casing 2 is provided in alinement with the dispatch tube 1, a gate or closure memberlO is provided which is hinged on the shaft 11 and is provided with a handle 12 by which it can be swung from the normal open position shown in Figure 2 of the drawing to the closed horizontal position shown in Figure 1 The closing: of the gate 10, fOllGWlllg t-li insertion of a carrier through the opening 8 into;

the adjacent end of the dispatch tubefll I operates also to unseat the valvedand to permit pressure fluid to flow into the chnnr her 7 and beneath the carrier positioned in dispatch tube 1. the pressure fluid serving to impel the carrier through the tube in an obvious manner. In order to lift the valve member 4 from its seat 5 upon the closingof the gate 10 a downwardly extending valve operating member 13 is provided. the lower end 14 of which is engaged by the gate as it is swung to its horizontal closed position. A suitable spring 15 placed between the bottom 9 of the casing 2 and the shouldered end member 14; of the valve operatprojecting edge 19 on the end of the gate 10 "to thereby lock the gate in its closed position aswill be clear. The other extremity o fthearm 16 is pivotally connected to a fi'exible diaphragm 20 which forms a wall enclosure for one side of the air pressure ehamber21 provided at oneend of the easing2. The'pressure chamber 21 is provided w ith an inlet port 22 through which pres- "'siirefiuid from the chamber 7 passes into chamber 21 and presses against the dia- "phragnr 2Q to hold the latch arm 16 in its gateholdingpositi'on.

' order to release the latching device 16 its holding engagement with the gate 10,,Wlin a suitable interval. of 7 time has .fe'la pseld to permit the carrier to travel "througlrthe dispatch tube 1, the following I 1 t'i'me controlled releasing mechanism is em- 'ployed, A yalve operating member 23 is jp votally mounted on a shaft 11 and is f ia'sed by the faction of a spring 30 to take ,a position such as is shown in Figure 2 of {the drawing wherein the extension 25 engages the valve stem 26 to-therebyoperate the valve 27 in a cylinder 28 and permit fp'r sure 'fluid to exhaust from the chamber 21 tli roughthe pipe 29 and port 45 to at nosphere andthereby permit the weight of fthej gate 10 to unlatch the edge 19 from the latching lug18 andallow the gate to swing t-1o it's'ver-tlcal open position as shown in "Ei V strict the-rotating movement of the valve 45 H tire- 2 of the 'drawing. In order to ret ng. member 23 under the force of the or 30,a piston stem 31 is pivoted .to the {actuating member 23 at the point 32, the fpiston stemlbeing directly connected to a pistonj33 operatingin a cylinder 34. It will bejseen ftha't theup-ward movement of the piston stem 31 is restricted by. the slow movement of the piston 33 which is so iformedas to offer considerable resistance to flu'pward movement in the cylinder.

y means ofjthis mechanism the rotating move- :ment pf the extension member 25 of the valve actuating member 23 from the horiz ontal position shown in Figure 1 to the VQIt-lCfil'pOSltlOn shown in Figure 2 1s retarded, since the member 25 cannot travel fasterlthanthe upward speed of travel of :the'piston stem 31 to which it is indirectly coupled. It will be clear that the slow movegnent of the member 25 to the position in which itengages the valve actuating stem portions of the cylinder 46. the double piston occupies an intermediate 26 provides an interval of time between the closing of the gate 10 and the opening of the valve 28 which may be fixed at a duration suiiicient to allow a carrier to travel through the length of the dispatch tube 1.

In order to release the valve actuating member 23 when the gate 10 is moved to its closed position, a holding awl 35 is pivoted on the gate 10 at the point 36, the upper end of the pawl 35 normally engaging a notch 37 formed in the adjacent end of the actuating member 23. A spring 38 acts to hold the pawl 35 in latching engagement with the notch 37. In order to release the latch from the notch 37 in the closed position of the gate 10, an actuating member 39 is provided which engages the lower surface 9 of the casing 2 as the gate 10 is moved into closed position and thereby causes the latching pawl 35 to be rotated in a clockwise direction in Figures land 2 and moved from its notch engaging position, as is clearly shown in Figure 1 of the drawing.

Preferably a stop member 40 is provided against which the gate member 10 abuts in moving to its open position. In the preferred form of the invention the gate member 10 is provided with a spring mounted closure member 41 provided with cushioning material 42 such as rubber to provide an air-tight closure connection with the edges of the opening 8 in the casing 2.

In order to prevent the dispatch of a carrier in the tube 1 when the fluidpressure in the system is either too low or too high for effective operation a device is provided for exhausting the chamber 21 during the existence of either abnormal pressure condition referred to and thereby preventing the holding'of the closure 11 in position a inst the opening 8 and preventing the bin din up of pressure behind the carrier to prope it through the tube. This safety device consists of a cylinder 46 communicating with the interior of the pressure supply tube 3 at 47 and with the connection 29 'fromthe chamber 21 at 18. A double piston 49 is mounted to reciprocate in the cylinder 46, fluid pressure entering the cylinder at 47 beneath the lower head 49 of the piston tending to move the piston upwardly in the cylinder, and the compression. spring 50 tween the upperpiston head 51 and the cap 52 of the cylinder tending to move the double piston downwardlyin the cylinder.

An outlet port 53 is connected through a branched tube 54 with vertically separated In operation,

position obstructing the outlet end of'the passage 48 and the port opening into the lower end of the branched tube 54. Upon the fall. of pressure below a predetermined limit, adjusted for by varying the position of the cylinder cap 52, the upper piston head 51 falls below the outlet port of the pipe 48 and air passes from the tube 48 through the cylinder d6 above the piston and through the pipe 54: to the port 53. On the other hand an undue rise oi pressure in the pipe 3 will elevate the double piston against the pressure of the spring 50 and lift the upper piston. head 51 above the port opening into the cylinder it from the pipe 48 to allow air in the pipe 48 to flow beneath the piston 51 and through. the lower end of the discharge pipe 5% to the port 53, as will be clear. In either case, the chamber 21 is exhausted and the latch 18 will not hold the gate 10 in closed position.

It will be seen that by means of the construction disclosedautomatic gate operating mechanism has been provided which will automatically bring the gate to open position at a predetermined interval of time after the gate has been closed. This interval of time is suflicient to permit of the passage of a carrier through the dispatch tube so that, it a carrier be immediately dispatched in the other end of the tube, which is provided vith terminal mechanism similar to that described, the gate mechanism at the end of the dispatch tube shown will be free of obstructing means with the result that the carrier can freely pass through the casing 2 and be discharged from the end of the dispatch tube 1; It will also be seen that the timing mechanism which is employed is wholly independent of the pressure fluid used in the tube system so that the objectionable effects of moisture, oil and the like in the pressure fluid are not met with in gate releasing mechanism of the type described.

What I claim is:

1. A terminal device for pneumatic dispatch tubes comprising a gate tending to take an open position and movable to a tube closing position, means for holding the gate in closed position, means operable by the movement of the gate to supply pressure fluid to said gate holding means and time cont-rolled means operating independ ently of the pressure conditions in the tube system for causing the holding means to release the gate at the end of a predetermined interval of time.

2. A terminal device for pneumatic dispatch tubes comprising: a gate tending to take an open position and movable to a tube closing position, fluid pressure operated means for holding the gate in closed position, means operable by the movement or" the gate to closed position to supply pressure fluid from the tube system to said gate holding means, and spring operated time controlled means for releasing the pressure in said gate holding means to release the gate at the end. of a predetermined interval of time.

3. A terminal device for pneumatic dispatch tubes comprising: a gate tending to take an open position and movable to a tube closing position, pneumatic means for holding the gate in closed position, spring operated time controlled means for releasing said gate holding means, said releasing means being released for operation when the gate has substantially reached closed position, whereby the gate will be released to move to open position at the end of a predetermined interval of time after it has been moved to closed position.

4. A terminal device for pneumatic dispatch tubes comprising: a gate tending to take an open position and movable to a tube closing position, fluid pressure operated means for holding the gate in closed position, spring operated time controlled means for releasing the pressure fluid from said holdingnieans, said releasing means being reset away from operating position and released for operation when the gate has reached closed position, whereby the gate will be released to move toopen position at the end of a predetermined interval of time after it has been moved. to closed position.

5. A. terminal device for pneumatic dis patch tubes comprising: a gate tending to tal-re an open position and movable to a tube closing position, fluid pressure operated means for holding the gate in closed position, means operable by the movement of thegate to closed position to supply pressure fluid from the tube system to said gate holding means, spring operated time controlled means for releasing the pressure fluid from said holding means, said releasing means being reset away from operating position the movement of the gate to closed position and released. for operation when the gate has reached closed position, whereby the will be released to move to open position at the end of a predetermined interval of time after it has been moved to closed position.

6. A terminal device for pneumatic dispatch tubes comprising: a gate tending to take an open position and movable to a tube closing position, means for holding the gate in closed position, a spring operated device for releasing the gate holding means, a latch carried by the gate and engageable with the spring operated device to place the spring under tension as the gate is moved to closed position, means for tripping the latch as the gate reaches closed position to allow said spring operated device to act, and a dash-pot retarding device operating to restrict the movement of said spring operated device whereby a predetermined interval of time will elapse before the holding means releases the gate.

7. A. terminal device for pneumatic dispatch tubes comprising: a gate tending to take an open position and movable to a tube closing position, fluid pressure oper ated means for holding the gate in closed alatch carried :by the gate and engageable with the spring actuated device to place the spring under tension as the gate is moved to closed position, means for tripping the latch-asthe gate reaches closed positionto allow said spring actuated device to act, and adash-pot retarding device operating to restrict the movement of said spring operated device, whereby a predetermined interval of time Will elapse before the gate holding means releases the' gate.

85A terminal device for pneumatic dispatch tubes comprising: a gate tending to take an open position and movable to a tnbe closing position, meains for holding the-gatei'in closed POSllZlOH, a device for releasing the gate holding means, a latch carried by the gate and engageable with the releasing means to place the releasing means in operable position as the gate is moved to closed position, means for tripping the latch as the gate reaches closed position to allow said releasing means to act, and a retarding device operating torestrict the movement of said releasing device whereby a predetermined interval of time will elapse before the gate holding means releases the gate.

9. A terminal device for pneumatic dispatch tubes comprising: a gate tending to take an open position and movable toa tube closing position, pneumatic means for holding the gate in closedposition, and time controlled means operating independently of thepressure fluid in the tube system for causing the holding means to release the gate atthe end of a predetermined interval of time.

JAMES G. MACLAREN. 

